A guy walks into a bar with a small dog. The bartender says, "Get out of here with that dog!"

The guy says, "But this isn't just any dog... this dog can play the piano!"

The bartender hooks a thumb over at a piano in the corner, "If that dog can play that piano, you both get a drink on the house!"

The guy sits the dog on the piano stool, and the dog starts playing.  Ragtime, Mozart... and the bartender and patrons are loving it.

Suddenly a bigger dog runs in, grabs the small dog by the scruff of the neck, and drags him out.  The bartender asks the guy, "What was that all about?"

The guy replies, "Oh, that was his mother.  She wanted him to be a dentist."